Repro Session 4 Flashcards
What is the adult remnant of the processus vaginalis in the male?
Tunica vaginalis
What are the two coverings of the testis?
Tunica vaginalis and tunica albuginea
What invaginates the testis and splits it into lobules with fibrous septae?
Tunica albuginea
Describe the descent of the testes.
7 wks: gonads develop retroperitoneally within mesonephric ridge. 7 months: descend through abdomen and cross inguinal canal 8 wks before delivery. 9 months: exit anterolateral abdominal wall taking layers with them
Why might a premature delivery lead to testes outside of the scrotum?
They don’t cross the inguinal canal until 8 weeks before delivery
What gives arterial supply to the testes?
Direct branch of the abdominal aorta, the testicular artery
Where does the venous drainage of the testes empty?
R testicular vein into IVC and L into L renal vein
What are the three components of the epididymis?
Head, body and tail
How does the epididymis connect to seminiferous tubules?
Via effect tubules ductules and rete testis
Describe the path of the spermatid cord.
Deep inguinal ring, lateral to inferior epigastric vessels via inguinal canal and superficial inguinal ring to posterior border of testis
What are the contents of the spermatic cord?
Testicular artery, cremastic artery, artery to vas, pampiniform plexus, genital branch of genitofemoral nerve, vas deferens, lymphatics and processus vaginalis
How does the pampiniform plexus aid spermatogenesis?
Veins forming it wrap around arteries to reduce blood temperature
What covering of the spermatic cord does the external abdominal oblique aponeurosis form?
External spermatic fascia
What forms the cremasteric muscle and fascia in the spermatic cord?
Internal abdominal oblique and transversalis fascia
What forms the internal spermatic fascia in the spermatic cord?
Transversalis fascia
What is the order of spermatic cord coverings from superficial to deep?
External spermatids fascia, cremasteric muscle and fascia, internal soermatic fascia
Why are indirect inguinal hernias often called congenital despite not presenting at birth?
Have a developmental basis
What is an indirect inguinal hernia?
Reopening of the processus vaginalis creating a potential continuity between the peritoneal cavity and the tunica vaginalis
Where does the spermatic cord usually twist in testicular torsion?
Just above the upper pole of the testis
What gives innervation to the anterior surface of the scrotum and testis?
Lumbar plexus
Where does the sacral plexus give innervation to in the scrotum and testis?
Posterior and inferior surfaces
Where does lymph from the testis drain to?
Paraaortic nodes
Why do the testis not drain to local lymph nodes?
Due to the developmental origin of the testis
Where does lymph from the scrotum drain?
Superficial inguinal nodes
Describe the passage of the ductus deferens.
Ascends in spermatic cord, inguinal canal, pelvic side wall, dilated ampulla, ejaculatory duct
What proportion of the ejaculate volume is secreted by the seminal vesicle?
70-80%
Where is the seminal vesicle positioned?
Retroperitoneal between the bladder and rectum at the diverticulum of vas deferens
What does the combination of the spermatic vesicle and vas deferens ducts form?
Ejaculatory duct
Describe the position of the prostate gland.
Base adjacent to neck of bladder, apex adjacent to urethral sphincter and deep perineal muscles, anterior surface adjacent to urethral sphincter, posterior adjacent to ampulla of rectum and inferolateral adjacent to levator ani
What divides the prostate into anatomical lobes?
Urethra and ejaculatory ducts as they pass through
What are the four anatomical lobes of the prostate gland?
Inferoposterior, inferolateral, superomedial and antero medial
Which anatomical lobes tend to be affected in BPH?
Superomedial and anteromedial
Where is the central zone of the prostate found?
Around ejaculatory ducts
What is the embryological origin of the central zone of the prostate?
Wolffian duct
Where is the transitional zone of the prostate found?
Centrally around the urethra
What is the embryological origin of the transitional and peripheral zones of the prostate?
Urogenital sinus
Where is the peripheral zone of the prostate found?
Forms the main body, located posteriorly
To which nodes might malignancy spread from the peripheral zone of the prostate?
Internal iliac or sacral
Describe the path a metastatic cancer may take in the venous drainage from the peripheral zone of the prostate.
Internal vertebral plexus through the vertebrae to the brain
Which zone of the prostate is examined by DRE?
Peripheral
What type of tissue makes up the prostate gland?
Fibromuscular
What are the three components of the penis?
Root, body and glans
What gives arterial supply to the penis?
Branches of internal pudendal arteries
What are the four parts of the male urethra?
Pre-prostatic, prostatic, membranous and spongy
What does the prostatic urethra receive?
Ejaculatory ducts
Why is the membranous urethra the least distensible portion of the male urethra?
Surrounding fibrous pelvic floor and perineum
What does the distal expansion of the ventral corpus spongiosum form?
Glans penis
What happens to the dorsal pair of corpora cavernosa during erection?
They swell with blood
How does ischiocavernous help maintain erection?
Compresses veins in the root
What does bulbospongiosus help to do in the male?
Expel last drops of urine and with autonomic supply maintains erection
Are ischiocavernosus and bulbospongiosus found in the male and female?
Yes
What are the contents of the labioscrotal folds?
Testis, epididymis, 1st part of spermatic cord
What can cause enlargement of the scrotum?
Inguinal hernia, hydrocoele, haematocoele, varicocoele, epipdidymitis
What is hydrocoele?
Serous fluid in the tunica vaginalis usually due to failure of the processus vaginalis to close
What is haematocoele?
Accumulation of blood in the tunica vaginalis
What is varicocoele?
Dilation of testicular veins
Why is varicocoele usually seen in the left?
Left testicular vein drains into the smaller L renal vein rather than the IVC
How are hydro- and haematocoele differentiated clinically?
Transillumination
What do the scarpa and camper layers of the abdominal wall become in the scrotum?
Darts fascia and muscle
Is the scarpa or camper layer of the SC tissue of the anterior abdominal membranous?
Scarpa
What are the corresponding scrotal coverings of the anterior abdominal wall muscles?
External oblique and its fascia –> external spermatic fascia. Internal oblique –> cremaster muscle. Fascia of superficial and deep internal obliques –> cremasteric fascia. Transversalis fascia –> internal spermatic fascia
What does the peritoneum become in the scrotum?
Tunica vaginalis
What gives the rugose appearance of the scrotum?
Smooth muscle fibres of dartos muscle
How does the dartos muscle help reduce heat loss when the scrotum is exposed to cold air?
Fibres contract causing scrotum to wrinkle. This thickens the integumentary layer, decreases surface area and helps the cremaster muscle to hold the testes closer to the body
What gives arterial supply to the scrotum?
Posterior scrotal branches of perineal artery (internal pudendal), anterior scrotal branches of deep external pudendal artery (femoral) and cremasteric artery (inferior epigastric)
What accompanies the arteries in the scrotum?
Scrotal veins
What suspends the testes in the scrotum?
Spermatic cord
Which testis is usually more inferior?
Left
What is the sinus of epididymis?
Slit-like recess of tunica vaginalis between the body of epididymis and posterolateral testis
What is the mediastinum of testis?
Thickened ridge of tunic albuginea on the internal posterior aspect of the testes that gives rise to fibrous septae that split the gonad info lobules
What are the rete testis?
Network of canals in the mediastinum of the testis
Describe the venous drainage from the testes to the IVC/ L renal vein.
Arise from testis and epididymis, into pampiniform plexus that converges superiorly to R and L testicular veins
Describe the passage of the testicular arteries.
Arise from anterolateral AA just inferior to renal artery and move retroperitoneally crossing the ureters, moving inferior to external iliac artery through the inguinal canal into the spermatic cord
What do the testicular arteries anastomose with?
Artery of ductus deferens